
<html>
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
	<link rel=stylesheet href='include/hoj.css' type='text/css'>
</head>
<body>
<center>
<div style="width:90%; text-align:left">
<img src="image/logo.png"/>
</div>
<table width=96%> 
	<tr align="center" class='hd' valign="top">
				<th><a href="faqs.php">F.A.Qs</a></th>
		<th><a href="./bbs.php">Web Board</a></th>
		<th><a href="./">Home</a></th>
		<th><a href="./problemset.html">ProblemSet</a></th>
		<th><a href="./status.php">Status</a></th>
		<th><a href="./ranklist.php">Ranklist</a></th>
		<th><a href="./contest.php">Contest</a></th>
		<th><a href=loginpage.php>Login</a></th><th><a href=registerpage.php>Register</a></th>	</tr>
</table>
</center>
<center>
<div class="notice">
	<div>
		<B>Notice:</B>鉴于种种原因，本OJ自下周星期一（3月5号）开始不再全面开放，请各位做好善后事宜，谢谢合作。	</div>
</div>
</center>
</div>
<title>Problem 1651. -- [Usaco2006 Feb]Stall Reservations -- 衡阳八中OJ离线版-2012-02-29</title><center><h2>1651: [Usaco2006 Feb]Stall Reservations</h2><span class=green>Time Limit: </span>10 Sec&nbsp;&nbsp;<span class=green>Memory Limit: </span>64 MB<br><span class=green>Submit: </span>279&nbsp;&nbsp;<span class=green>Solved: </span>147<br>[<a href='submitpage.php?id=1651'>Submit</a>][<a href='problemstatus.php?id=1651'>Status</a>][<a href='bbs.php?id=1651'>Discuss</a>]</center><h2>Description</h2><div class=content>Oh those picky N (1 <= N <= 50,000) cows! They are so picky that
each one will only be milked over some precise time interval A..B
(1 <= A <= B <= 1,000,000), which includes both times A and B.  Obviously,
FJ must create a reservation
system to determine which stall each cow can be assigned for her
milking time. Of course, no cow will share such a private moment
with other cows.

Help FJ by determining:
* The minimum number of stalls required in the barn so that each
  cow can have her private milking period
* An assignment of cows to these stalls over time

有N头牛,每头牛有个喝水时间,这段时间它将专用一个Stall
现在给出每头牛的喝水时间段,问至少要多少个Stall才能满足它们的要求</div><h2>Input</h2><div class=content>* Line 1: A single integer, N

* Lines 2..N+1: Line i+1 describes cow i's milking interval with two
        space-separated integers.

</div><h2>Output</h2><div class=content>* Line 1: The minimum number of stalls the barn must have.

* Lines 2..N+1: Line i+1 describes the stall to which cow i will be
        assigned for her milking period.

</div><h2>Sample Input</h2>
			<div class=content><span class=sampledata>5<br />
1 10<br />
2 4<br />
3 6<br />
5 8<br />
4 7<br />
</span></div><h2>Sample Output</h2>
			<div class=content><span class=sampledata>4<br />
<br />
<br />
OUTPUT DETAILS:<br />
<br />
Here's a graphical schedule for this output:<br />
<br />
Time     1  2  3  4  5  6  7  8  9 10<br />
Stall 1 c1>>>>>>>>>>>>>>>>>>>>>>>>>>><br />
Stall 2 .. c2>>>>>> c4>>>>>>>>> .. ..<br />
Stall 3 .. .. c3>>>>>>>>> .. .. .. ..<br />
Stall 4 .. .. .. c5>>>>>>>>> .. .. ..<br />
<br />
Other outputs using the same number of stalls are possible.</span></div><h2>HINT</h2>
			<div class=content><p>不妨试下这个数据,对于按结束点SORT,再GREEDY的做法<br />
1 3<br />
5 7<br />
6 9<br />
10 11<br />
8 12<br />
4 13<br />
正确的输出应该是3</p></div><h2>Source</h2>
			<div class=content><p><a href='problemset.html?search=Silver'>Silver</a></p></div><center>[<a href='submitpage.php?id=1651'>Submit</a>][<a href='problemstatus.php?id=1651'>Status</a>][<a href='bbs.php?id=1651'>Discuss</a>]</center>﻿<br>

<a href="./"><span class=red>HOME</span></a>
<a href="javascript:history.go(-1)"><span class=red>Back</span></a>

<hr>
<center>
	<div class="footer">
			<a href=setlang.php?lang=ko>한국어</a>&nbsp;
		<a href=setlang.php?lang=cn>中文</a>&nbsp;
		<a href=setlang.php?lang=fa>فارسی</a>&nbsp;
		<a href=setlang.php?lang=en>English</a>&nbsp;
		<a href=setlang.php?lang=th>ไทย</a>
	<br>		<div>版权所有 &copy;2008-2012 WaterPark Organization. | <script src="http://s21.cnzz.com/stat.php?id=2982771&web_id=2982771" language="JavaScript"></script>
</div>
		<div>Based on opensource project <a href="http://hustoj.googlecode.com">hustoj</a>.</div>
	</div>
</center>
</body>
</html>
